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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

24564 results found.

  1. LIGO/Virgo/KAGRA S230708z: Identification of a GW compact binary merger candidate
  2. LIGO/Virgo/KAGRA S230708t: Identification of a GW compact binary merger candidate
  3. IceCube-230707A: No candidates detected by Swift-XRT
  4. GRB 230709C: AstroSat CZTI detection
  5. LIGO/Virgo/KAGRA S230708cf: Updated Sky localization
  6. GRB 230707B: CALET Gamma-Ray Burst Monitor detection
  7. GRB 230709C: BALROG localization (Fermi Trigger 710617111 / GRB 230709735)
  8. LIGO/Virgo/KAGRA S230707ai: Updated Sky localization
  9. IceCube-230707A: No candidates from the Zwicky Transient Facility
  10. Fermi-LAT gamma-ray observations of IceCube-230708A
  11. Fermi-LAT gamma-ray observations of IceCube-230707B
  12. Fermi-LAT gamma-ray observations of IceCube-230707A
  13. LIGO/Virgo/KAGRA S230630am: Updated Sky localization
  14. LIGO/Virgo/KAGRA S230630am: Updated Sky localization
  15. GRB 230709B: BALROG localization (Fermi Trigger 710614579 / GRB 230709706)
  16. IceCube-230708A: Upper limits from a search for additional neutrino events in IceCube
  17. IceCube-230707B: Upper limits from a search for additional neutrino events in IceCube
  18. IceCube-230707A: Upper limits from a search for additional neutrino events in IceCube
  19. LIGO/Virgo/KAGRA S230709bi: Identification of a GW compact binary merger candidate
  20. Swift Trigger 1178410: possible GRB 230709A
  21. LIGO/Virgo/KAGRA S230708cf: Identification of a GW compact binary merger candidate
  22. GRB 230628C: GRID Detection
  23. IceCube-230708A - IceCube observation of a high-energy neutrino candidate track-like event
  24. GRB 230707B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  25. IceCube Alert 230708.35: Global MASTER-Net observations report
  26. IceCube-230707B - IceCube observation of a high-energy neutrino candidate track-like event
  27. GRB 230707B: Fermi GBM Final Real-time Localization
  28. IceCube Alert 230707.71: Global MASTER-Net observations report
  29. IceCube-230707A - IceCube observation of a high-energy neutrino candidate track-like event
  30. GRB 230707A: Fermi GBM Detection
  31. LIGO/Virgo/KAGRA S230707ai: Identification of a GW compact binary merger candidate
  32. GRB 230707A: Swift/BAT-GUANO arcminute localization of a burst
  33. Fermi GRB 230707A: Global MASTER-Net observations report
  34. GRB 230707A: Fermi GBM Final Real-time Localization
  35. LIGO/Virgo/KAGRA S230706ah: Updated Sky localization
  36. Integral GRB230706.70: Global MASTER-Net observations report
  37. LIGO/Virgo/KAGRA S230704f: Updated Sky localization
  38. LIGO/Virgo/KAGRA S230630bq: Updated Sky localization
  39. IBAS trigger number 10311: not a real GRB
  40. LIGO/Virgo/KAGRA S230702an: Updated Sky localization
  41. GRB 230625A: Detection by GRID
  42. LIGO/Virgo/KAGRA S230529ay: Updated Sky localization and EM Bright Classification
  43. LIGO/Virgo/KAGRA S230706ah: Identification of a GW compact binary merger candidate
  44. LIGO/Virgo/KAGRA S230627c: GECKO optical follow-up observations of host galaxy candidates and ZTF23aaptsuy/AT2023lxu
  45. Fermi trigger No 710117592: Global MASTER-Net observations report
  46. GRB 230626A: VZLUSAT-2 detection
  47. LVK S230619bd/GBM-230619: Upper limits from a two-week IceCube neutrino search
  48. LIGO/Virgo/KAGRA S230704f: Identification of a GW compact binary merger candidate
  49. Konus-Wind detection of GRB 220623A
  50. LIGO/Virgo/KAGRA S230627c: observations of ZTF23aaptsuy/AT2023lx in AbAO observatory
  51. LIGO/Virgo/KAGRA S230702an: Identification of a GW compact binary merger candidate
  52. GRB 230628E: Swift-BAT refined analysis
  53. GRB 230702A: Fermi GBM Final Real-time Localization
  54. GRB 230701A: Fermi GBM Final Real-time Localization
  55. LIGO/Virgo/KAGRA S230627c: GRANDMA observations of galaxies and ZTF counterpart candidates
  56. LIGO/Virgo/KAGRA low-significance gravitational wave candidate S230701z: one counterpart neutrino candidate from IceCube neutrino searches
  57. LIGO/Virgo/KAGRA S230627c: Upper limits from Swift/BAT-GUANO
  58. LIGO/Virgo/KAGRA S230630bq: Identification of a GW compact binary merger candidate
  59. IPN triangulation of GRB 230625B (ultra-long)
  60. LIGO/Virgo/KAGRA S230630am: Identification of a GW compact binary merger candidate
  61. GRB 230628E - VLT spectroscopic observations
  62. Fermi GRB 230628C: Global MASTER-Net observations report
  63. GRB230628E: VLT optical identification of afterglow candidate
  64. Fermi GRB 230628D: Global MASTER-Net observations report
  65. LIGO/Virgo/KAGRA S230628ax: Identification of a GW compact binary merger candidate
  66. GRB 230628E: LCOGT Optical Upper Limit
  67. Swift GRB230628.93: Global MASTER-Net observations report
  68. GRB 230628D: BALROG localization (Fermi Trigger 709676556 / GRB 230628849)
  69. GRB 230628D: Fermi GBM Final Real-time Localization
  70. LIGO/Virgo/KAGRA low-significance gravitational wave candidate S230628aj: one counterpart neutrino candidate from IceCube neutrino searches
  71. GRB 230628C: Fermi GBM Final Real-time Localization
  72. GRB 230628B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  73. GRB 230623B: CALET Gamma-Ray Burst Monitor detection
  74. LIGO/Virgo/KAGRA S230516az: GOTO candidate counterpart GOTO23hu ruled out by Zwicky Transient Facility observations
  75. ZTF23aaoohpy /AT2023lcr: TNG NIR detection
  76. GRB 230628A: Fermi GBM Final Localization
  77. LIGO/Virgo/KAGRA S230627c: Additional observations from the Zwicky Transient Facility
  78. GRB 230626A: GRBAlpha detection
  79. LIGO/Virgo/KAGRA S230527c: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  80. LIGO/Virgo/KAGRA S230627c: ATLAS information on the ZTF candidates
  81. LIGO/Virgo/KAGRA S230627c: Upper limits from Fermi-GBM Observations
  82. GRB230626A: Fermi GBM Detection
  83. LIGO/Virgo/KAGRA S230627c: Global MASTER-Net observations report
  84. LIGO/Virgo/Kagra S230627c: NED Galaxies in the Localization Volume
  85. Konus-Wind detection of GRB 230616A
  86. LIGO/Virgo/KAGRA S230627c: Zwicky Transient Facility observations and candidates
  87. LIGO/Virgo/KAGRA S230627c: Coverage and upper limits from MAXI/GSC observations
  88. LIGO/Virgo/KAGRA S230627c: Updated Sky localization and EM Bright Classification
  89. LIGO/Virgo/KAGRA S230627c: Identification of a GW compact binary merger candidate
  90. GRB 230618A: Swift-BAT refined analysis
  91. GRB 230625B: Swift/BAT-GUANO detection of a long burst
  92. LIGO/Virgo/KAGRA S230624av: Updated Sky localization
  93. GRB 230622A: Swift-BAT refined analysis
  94. GRB 230623A: Swift-XRT observations
  95. GRB 230625A: Fermi GBM Final Real-time Localization
  96. INTEGRAL upper limit on any GRB associated with ZTF23aaoohpy/AT2023lcr
  97. GRB 230623B: Swift/BAT-GUANO detection of a long burst outside the coded FOV 
  98. LIGO/Virgo/KAGRA S230624av: Identification of a GW compact binary merger candidate
  99. IceCube-Cascade 230622A: Upper limits from a search for additional neutrino events in IceCube
  100. Swift GRB 230622A: Global MASTER-Net observations report

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